In general, a magnetic tape for audio use, video use or the like is on sale in a manner to be housed in a cassette casing while being wound on a pair of reel hubs. Manufacturers each prepare various kinds of tape cassettes in which magnetic tapes of lengths predetermined according to various standard specifications for each grade are wound on the reel hubs. For example, audio tape cassettes in which various magnetic tapes of lengths corresponding to the amounts of recording time such as a forty-six-minute tape, a sixty-minute tape and a ninety-minute tape, as well as a fifty-four-minute tape, an eighty-minute tape and the like are housed are standardized and commercially available for each grade. Users selectively buy such audio tape cassettes as intended.
Unfortunately, the users are merely permitted to purchase only tape cassettes including magnetic tapes of lengths defined in the standard specifications, resulting in being forced to purchase a tape cassette in which a somewhat long tape is housed although they know well that at least a part of the tape will be in vain. In particular, in view of the present situation that sources of data to be recorded are substantially diversified, it would be highly difficult or substantially impossible to provide a tape cassette which meets user's requirements and minimizes the portion of a magnetic tape which is out of use. For example, when the time length of a recorded source is slightly larger, for example, in an amount less than one minute, than that of a magnetic tape defined by the standard specifications, an additional tape is required to record the excessive portion of the recorded source. This results in a large part of the additional tape being out of use. Also, this causes latency time to be substantially increased when the tape is to be played back. Further, this causes a user to feel displeasure during the playing-back, because the additional tape substantially exhibits a soundless condition wherein only noise is generated therefrom. It would be considered that such a disadvantage is eliminated by providing a tape cassette including a magnetic tape having a length corresponding to a short period of recording time such as, for example, a one-minute magnetic tape. However, such an approach causes not only the manufacturing and distributing costs to be highly increased, resulting in being uneconomical, but excessive kinds of tape cassettes to be placed on the market to render both selection of tape cassettes by the user and handling of tape cassettes by suppliers extremely troublesome and time-consuming.